


And that's why you should read the medical prescriptions

by Simpknight



Category: Fate/Grand Order
Genre: Breastfeeding, Denial, Dom/sub Undertones, Lactation Kink, Multi, POV Second Person, Plot What Plot/Porn Without Plot, Potions, Potions Accident, The Author Regrets Nothing
Language: English
Status: Completed
Published: 2021-03-13
Updated: 2021-03-13
Packaged: 2021-03-21 05:55:13
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,576
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/30017172
Author URL: https://archiveofourown.org/users/Simpknight/pseuds/Simpknight
Summary: Working for Paracelsus in exchange of QP sounds better than it actually is.
Relationships: Gawain | Saber/Reader
Kudos: 6





	And that's why you should read the medical prescriptions

**Author's Note:**

> I apologize in advance for this.  
> It all started as a random idea but this type of clichés are my favorite so... Yeah
> 
> Before starting: there's mentions of breast and menstruation, but aside from that all terms used for the reader are gender neutral

“So… You promise this is 100% safe, right?”  
You carefully examined the small bottle and its cerulean liquid. It was thicker than water but not as viscous as syrup.  
“Well, I’ve done enough tests with other subjects to determine that it’s harmless, it should be ok. Still, I have to detect if it causes any side effects, we don’t want to repeat what happened last time, do we?”  
“I mean; it wasn’t that bad, you aren’t always able to glow in the dark. Mash was pretty mad, though.”  
You shook a bit the content, examining further under the light. It didn’t look suspicious. Also, you knew that, besides Paracelsus reputation, he wouldn't harm his master, just as any servant at Chaldea.  
"Anyway, what is this supposed to be?"  
"If it works as I expect, it will be a mana buster. Chaldea can provide enough mana to all servants without any problems, but it may occur a situation in which you could be in need of transfer your energy. This could help you to restore your mana or help your servants on difficult situations."  
"Eh~? You sure are cautious... Well, I have no objection whatsoever, but first things first; where's my payment?"  
The alchemist giggled at your impatience.  
"Ok, fair enough, I'll pay you first. Is 6 million QP enough for you?"  
"Wha... Wait, 6 million?"  
"Well, you told me you were saving for something special, right? Consider this a token of gratitude for being my test subject."  
"Thank you so much! I promise I'll get you to third ascension as soon as I can!"  
With that said you drank the strange liquid, just a gulp in case Paracelsus needed to make any changes on the composition. Now you only had to wait and see if something changed.  
From time to time he would ask you if you felt something different or if you were sick. After half an hour he decided to conclude the test, after all it was getting late (since you sneaked in his room after dinner so Mash wouldn't yell at you for acting imprudently). Before leaving, he asked you to keep him updated in case something happened.  
When you got to your room you let yourself fall in the mattress, exhaustion hitting you like a truck. It had been a hard week, working nonstop, but finally you got the amount of QP you needed. Hard work totally paid off.  
Sitting at the edge of the bed you started taking of your clothes to put on your pajamas. It was then when you realized your body was feeling kind of heavy, specially your chest. You cupped it gently in your hands; you weren't on your period but you could feel it was a bit bigger. So either hell was coming soon than expected or your body was begging you to sleep. Maybe both. Right now the only thing you could think of was rest, get some nice 8 hours of sleep in case that was possible and stop thinking for a bit.  
But apparently that was too much to ask for, because just as you covered yourself with the bed sheets someone knocked at the door.  
"Maybe if they think I'm asleep-"  
"Master, may I come in? I was hoping to talk with you if you're not busy"  
"I actually was busy, trying to sleep..." you mumbled to yourself, getting out of bed "Sure, come in... Oh, Gawain, it was you."  
Honestly, if it was anyone else you would be really mad. For him you could make an exception.  
"I'm sorry to disturb you this late at night, you didn't come to train this morning so I wanted to check on you."  
"OW, look at that." you rested your hands on your hips and puffed your chest up a bit, trying to look superior "You didn't see me for a day and you're already missing me? I was unaware of the effect I had on people."  
He laughed at your response.  
"Don't worry, I actually didn't, specially since I saw you already twice entering on Paracelsus room." his expression changed completely, you couldn't remember the last time he looked that disappointed "Mash asked me to keep an eye on you because she knew you've been helping him by being his _Guinea Pig_ as she claimed. Anything to say about that?"  
"... Oops?"  
"Seriously, what were you thinking?"  
"Oh, come on! They were safe experiments with some kind of weird inconveniences, I was just helping and he paid me for it, I needed that QP!"  
"If you needed it that bad then you could have asked me for help instead of putting yourself at risk. "  
"I... couldn't..."  
"Master, I've been serving you for a long time now. Is there any reason why you can't trust me? As a knight I have the duty to protect you, so for me it would be unforgivable if you were hurt, specially over such a trivial matter as collecting materials-"  
"They were for your skill upgrade." You bluntly confessed.  
The saber just stared silently at you, trying to process the information.  
"Excuse me?"  
"Listen, this week I was working so hard to get materials because I wanted to finally level your skills at maximum level. I've even been saving 3 crystallized lore for it! But you know how much you need for that kind of update? 10 million EACH!! That means 30 MILLION FOR 3 SKILLS!! SO YEAH, I COULDN'T ASK YOU FOR HELP BECAUSE IT WAS A SURPRISE AND THE ONLY THING I COULD DO WAS ASKING PARACELSUS. AND WHAT IT PISSES ME OFF THE MOST IS YOU COMING AND TELLING HOW IRRESPONSIBLE I AM FO- WHA-!"  
Gawain's strong arm wrapped around your body, hugging you tightly. His grasp was so firm it almost drew your breath away. It wasn't unpleasant having him holding you though.  
"Oh my, you should have told me sooner! I'm so happy right now... I need to repay you for being so generous with me."  
"Does that mean you'll stop scolding me?"  
Automatically, he ended the hug just to cross his arms, giving you that disapproving look again.  
"No. Even if your motives were good that's no reason to act how you acted... Uh... Master?"  
"What? You've got anything more to complain about my lack of self-awareness?"  
"That's not it! Just... How to explain...? Your shirt..."  
"Yes?"  
"It's wet. Around your chest."  
"Uh?"  
You looked down to realize you had some small spots on what you thought it was the areola area. The stain was still humid so it was something recent, but how did you get wet? Gawain's armor wasn't humid and it wouldn't leave those kind of marks.  
Lifting your shirt up, you touched one of your breasts to confirm that all your skin was dry except the nipple.  
"It doesn't look as if it's bleeding so that's a relief. It's not a wound so unless this is one of the potions side effects I have no clue what to do-Why are you staring at the wall?"  
The man coughed, not bothering to turn around.  
"It is no proper for a knight to stare."  
"Wow, what a gentleman!"  
"You're sarcasm is pretty sharp today."  
"It's been a long day, I just wanted to go to sleep and I suddenly find myself segregating some kind of weird liquid. So yes, I'm quite pissed."  
 _Wait a minute... Maybe..._  
You pinched gently one of your nipples. A tiny drop of some whitish substance dripped from there to your index finger, so you decided to smell it.  
"Master, what are you doing?"  
"What does it look like? Besides, weren't you busy with your gentlemanly act?"  
He didn't answer. You knew he tried to act all cool and steady when he actually was worried about your condition.  
 _Please tell me I'm wrong. It cannot be what I think it is._  
And with that, you licked it from your finger.  
"Master, now I'm seriously concerned about how you're acting!"  
"It's milk." you mumbled "I'm segregating milk."  
You sat on your bed, assimilating the situation in silence while Gawain stared at you, dumbfounded.  
"I'm going to kill Paracelsus." you said after a couple of minutes  
"Wait, wait... Are you completely sure it's not anything else?"  
"I fucking now how milk tastes like, ok? God, why couldn't it be the glowing in the dark thing again? This is fucking disgusting."  
"Well, it's not as bad as it looks like. I mean, it's something normal that happens when people get pregnant-"  
"YOU WOULDN'T SAY THAT IF YOU WERE ON MY POSITION! THIS IS ONE OF THE GROSSEST THINGS THAT CAN HAPPEN TO DE HUMAN BODY!"  
"You're exaggerating"  
"Only animals should produce milk... This is like a curse. Is karma paying me back for something I did? Other kind of punishment would be better than this."  
"What kind of potion could make something like that? I really doubt that alchemist's purpose was this."  
"Of course not! Listen, he told me it was some kind of mana buster. Like, it should help me or my servants to recover energy on dangerous situations."  
"Did you feel anything when you tried the milk?"  
"Eh? No, nothing weird. I mean, my body feels sore but that must be because I'm tired. Why?  
"You said it was supposed to be used to transfer mana so, maybe you can do it by... You know..."  
"Oh no, uh-uh. Don't even think about it."  
"I'm just saying it's a possibility. Besides..." he paused, trying to choose his words carefully "assuming that your body aches as a side effect of the elixir, it should be best to get rid of it."  
"I'm not a cow, Gawain."  
"That's not what I meant! It's just-"you interrupted him by cupping his face between your hands and pulling him closer.  
"I'm gonna say this slowly, so pay attention:" you said, squeezing his cheeks "try thinking with just one of your heads, because at this point I don't know if what's talking is your confused brain or your rising blood pressure."  
He blushed wildly, feeling exposed.  
"Ok, maybe I wasn't thinking clearly."  
"You think?"  
"But see it from this point: either you take care of that now or you wait until tomorrow and tell Paracelsus about it."  
"There's nothing wrong with the second option, I'm supposed to inform him in case things go wrong."  
"That's true, the only inconvenience is he'll have to analyze it, which means he'll probably have to, bluntly speaking, milk it somehow."  
…  
Oh.  
You didn't think about it. That would probably be even more embarrassing than this.  
"Let's say that supposedly you're right, nothing warranties I won't keep producing it."  
"It's worth the try, after all I doubt the effects will be permanent. And even if you stopped, what's been produced will still be there, so better to get rid of it as soon as possible."  
"You sure think a lot for a horny brained." You sighed "Ok, you win, this will be less embarrassing than asking Paracelsus for help. I'm doing this because I trust you, however we're doing this by my rules so you're not allowed to do anything else unless I agree to it, got it?"  
Gawain nodded as he picked you up and changed positions, sitting you on his lap. His hands swiftly roamed under the shirt, trying to lift up the fabric; still they were stopped by you own hands. You made yourself clear once more, if he wasn't going to listen then there was no point in continuing. Fortunately for him, he soon understood what you wanted, so he rested his hands on your hips, waiting for the next move.  
You kissed his forehead, letting him know he did good and then proceeded to take off your shirt. Moving you body closer, you continued by kissing his neck, leaving small bite marks whenever you felt like it. The knight quickly became impatient, his grip on your hips stronger than before. Maybe it was time to play nicely.  
You surrounded his neck with your arms, as a signal that he could continue from that point on. At first he mimicked your movements, leaving a trail of kisses from your neck to your cleavage. Then, he finally moved to your left nipple, rolling his tongue over it.  
It was weird feeling the hot saliva over your skin. With a sigh, you stroked his blonde locks, observing how he started sucking at a slow pace. You bit your lip, trying to hold your breath; it could possibly be another side effect of the potion or even a reaction to the new stimulation, but you were more sensitive than before.  
He kept drinking the liquid for a while and you swore you could feel how the weigh on your chest was slowly decreasing. When he was satisfied (or rather when the milk ran out), he let go, leaving a small trail of saliva. Licking his lips, he looked up at you, waiting for anything you had to say.  
"So... How are you feeling?"  
"Honestly? It feels as if I drank 3 cups of coffee, my chest is beating up really fast."  
"It could be that you actually don't have any need to get more mana and your body is reacting like this. Maybe we should stop."  
"No! I'm... I'm fine, I swear."  
"You sure? It doesn't really sound like that to me..."  
"There's no need to worry about me, Master, your condition is more important than mine."  
"Well, I'm feeling better than before, but that's no excuse. Please, promise me that you'll stop if you start feeling bad."  
"I promise." he said, breathing heavily on your chest.  
As quickly as he finished the sentence, he proceeded to give some attention to the other nipple, not even letting you complain about his impatience. This time, Gawain's pace was faster than before, it almost worried you. Almost. You soon understood the sudden impetuosity; he moved his hips involuntarily and you could feel the bulge forming in his pants.  
"Gawain, what are you doing?"  
"Master, I..." he tried to collect himself, failing miserably "I'm sorry, it's just... I can't help it, I need to-"  
"Gawain," you raised his chin up "I told you before you weren't allowed to act on your own without permission, right?"  
"But- "  
"If you need to you can use the shower, I won't help you from this point so you should take care about that alone."  
"… Yes, Master."  
You picked your shirt from the floor, leaving his lap. As soon as you saw him closing the shower door you let yourself fall in bed. You were really tired even knowing that Gawain did all the job. Without realizing, you fell asleep with the sound of the shower in the background.  
Some minutes passed until you opened your eyes again, when Gawain lied by your side, pulling you closer.  
"Did I wake you up?"  
"Nah, don't worry. You feeling better?"  
"Yes, much better. I don't think I'll be able to sleep though."  
You rested your head on his chest to feel his heart beat.  
"Wow, it sure goes fast. Guess you'll need to tell Paracelsus tomorrow."  
"What do you mean?"  
"You're going to tell me you didn't think that after drinking that you would have to accompany me inform him about the hole thing?"  
His silence was enough to answer your question.  
"So you didn't, what a surprise."  
"Do I really have to go?"  
"Oh you sure do."


End file.
